From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.4 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 91CF4C48BD3 for ; Wed, 26 Jun 2019 20:55:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 614CB2086D for ; Wed, 26 Jun 2019 20:55:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=ziepe.ca header.i=@ziepe.ca header.b="TBi220P0" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726341AbfFZUzB (ORCPT ); Wed, 26 Jun 2019 16:55:01 -0400 Received: from mail-pl1-f193.google.com ([209.85.214.193]:46193 "EHLO mail-pl1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726227AbfFZUzA (ORCPT ); Wed, 26 Jun 2019 16:55:00 -0400 Received: by mail-pl1-f193.google.com with SMTP id e5so2064624pls.13 for ; Wed, 26 Jun 2019 13:55:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ziepe.ca; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=bMxdvEdLjD1A9AKJa7buamnua6ndE13zHk8/3SA0xpk=; b=TBi220P0cqoilOs0VNo/aK3h3vIh4DHqMWYM3/xsM7rxg8vRC9vB3FeKKle7xEF+Ub c/A2Ia6QYlSw7cwbMBQyfBdYv54uyZ6xKUQ+QkDRfgWgo5RypRkGjFaWm2ykPW6JTo8F AnNSsV+rqWfslkCLRdq/e71/2TQZYL1quvSzRdMEfoUwlhYKvfJFQIhaWQUK4ia+k7eR cgPQ5KRJ0Rg5DrgjBR3TmHFiMZKA7Ljeag/N58i2HxUNVWt0ybAgynqXMm44Jvtl115E cwHup5Tv7BqDlSNc2j2kshgnuFrTydujMQM6+FISacSwwNM9jBiIB0QzVlt2S/qrgn6h p0yA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=bMxdvEdLjD1A9AKJa7buamnua6ndE13zHk8/3SA0xpk=; b=ufxN8otj6gxkc/OpMPrTHBaMzb7r4m2ZB6zdMmS8xZnq+R7Z2Cnhc/FNee1dZmh1YX EeAhjZQlpADpMpUCsatWdT92Fgyoo8QpzIbk9mPPw83EyCCl4rIMhTnns0PPMVBZTIQN QMGDbDFTzFvUyXHyyCUzZcpxhaBK+XNqZVSVo58uIaOawlGpuqXTSqcGenHZ1fgSMKsP XBWnq1bLqND848M00wivi8eT5qQzC7KFxA9tJbKNMM9SL1QTks7uS7Bg2dLE40tuSbNS mgpwZpXry39F/8kci5kd+ziL0SG+/D/HOo3Yb7yGfNUHJ7B82jL0z+uJ7afsS0kozhpN JgAA== X-Gm-Message-State: APjAAAUeJRo/CDMz34x3hUyOsCm9B3qcmGIIzrHvx+FrkNCEUtXab4w5 zAgpzHwItEBlXimqbwS5AhXwfg== X-Google-Smtp-Source: APXvYqzgDH5/ikCzES5M0MRO5K7K3ifgbGjP1mRuUaIUZdDHCGw68bO7qf91SGAx47qMnghFOmD8Fw== X-Received: by 2002:a17:902:9a87:: with SMTP id w7mr65029plp.221.1561582500008; Wed, 26 Jun 2019 13:55:00 -0700 (PDT) Received: from ziepe.ca ([148.87.23.38]) by smtp.gmail.com with ESMTPSA id t13sm3856107pjo.13.2019.06.26.13.54.59 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 26 Jun 2019 13:54:59 -0700 (PDT) Received: from jgg by jggl.ziepe.ca with local (Exim 4.90_1) (envelope-from ) id 1hgEwU-0001lK-9d; Wed, 26 Jun 2019 17:54:58 -0300 Date: Wed, 26 Jun 2019 17:54:58 -0300 From: Jason Gunthorpe To: Dan Williams Cc: Logan Gunthorpe , Christoph Hellwig , Linux Kernel Mailing List , linux-block@vger.kernel.org, linux-nvme@lists.infradead.org, linux-pci@vger.kernel.org, linux-rdma , Jens Axboe , Bjorn Helgaas , Sagi Grimberg , Keith Busch , Stephen Bates Subject: Re: [RFC PATCH 00/28] Removing struct page from P2PDMA Message-ID: <20190626205458.GA6392@ziepe.ca> References: <20190624072752.GA3954@lst.de> <558a27ba-e7c9-9d94-cad0-377b8ee374a6@deltatee.com> <20190625072008.GB30350@lst.de> <20190625170115.GA9746@lst.de> <41235a05-8ed1-e69a-e7cd-48cae7d8a676@deltatee.com> <20190626065708.GB24531@lst.de> <20190626202107.GA5850@ziepe.ca> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Wed, Jun 26, 2019 at 01:39:01PM -0700, Dan Williams wrote: > Hmm, that sounds like dev_pagemap without the pages. Yes, and other page related overhead. Maybe both ideas can exist in the pagemap code? All that is needed here is to map a bar phys_addr_t to some 'bar info' that helps the mapping. Jason